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Date: Wed, 25 Sep 2013 11:21:46 +0530
From: Sourav Poddar <sourav.poddar@ti.com>
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To: Huang Shijie <b32955@freescale.com>
Subject: Re: [PATCH] drivers: mtd: m25p80: Add quad read support.
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On Wednesday 25 September 2013 11:18 AM, Huang Shijie wrote:
> 于 2013年09月24日 20:10, Sourav Poddar 写道:
>> +    flash->quad_read = false;
>> +    if (spi->mode&&  SPI_RX_QUAD) {
>> +        quad_enable(flash);
>> +        flash->mtd._read = m25p80_quad_read;
>> +        flash->quad_read = true;
>> +    } else
>> +        flash->mtd._read = m25p80_read;
> How do you know the NOR support the QUAD read? by the spi->mode?
>
> i think you'd better add a DT node such as "m25p, quad-read".
no need to add a new property, support is already there.

If you see spi.c, "spi-rx-bus-width" property is already added. We will 
set this
property in dts to 4 in case of quad read. Once this is set, spi->mode will
be set to SPI_RX_QUAD in spi.c. which can be used by mtd layer to device 
whether
flash supports quad read or not.
>
> thanks
> Huang Shijie
>